


Equilibrium (a physics experiment)

by CarolineShea



Category: Glee
Genre: BDSM, M/M, Safeword Use
Language: English
Status: Completed
Published: 2017-04-03
Updated: 2017-04-03
Packaged: 2018-10-14 11:54:50
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 1,895
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/10535946
Author URL: https://archiveofourown.org/users/CarolineShea/pseuds/CarolineShea
Summary: Blaine wants to try an experiment. Kurt is uncomfortable from the start and ends up having to use his safeword. Contains non-graphic BDSM experimentation (specifically striking with a belt.)





	

 

 "I really want to try this," says Blaine softly, eyes wide and earnest. “Will you let me?”

 

**_0000_ **

 

The steady ticking of the classroom clock matches the pounding of Kurt’s heart.

The breeze from the open window flutters the pages of his notebook; the paper rustles and flips to an earlier entry, a page covered in practice equations and the results of a lab experiment.

He tries to find the page he’d been on and encounters a different sort of experiment; a few cautiously-scripted attempts at a name: _Kurt Hummel Anderson_ , he’d written. And then: _Kurt E. H. Anderson._ _Kurt E. Hummel-Anderson._ _Kurt Elizabeth Hummel-Anderson._

Kurt looks up at the clock again and swallows, throat dry, when he notices that it’s now past 2:30. Class ends at 2:47 and Blaine is meeting him at his house at 4:00.

There is a faint flutter of unease in his stomach that he’d been unable to shake; twisting tendrils of uncertainty that had first crept into him on Sunday, when Blaine had suggested _it ..._ and Kurt had agreed to it.

He’d _agreed_ to it, he reminds himself as his physics teacher, Ms. Hautz, begins writing on the whiteboard.

“You’ll want to copy down these definitions,” she tells the class.

Kurt curls his fingers around his pen. The slight sheen of sweat on his palm makes it slide right of his grasp and he has to reach for it again, fingers tapping against the desk nervously.

Her voice floats out over them. “This information _will_ be on the test.”

 

**_0000_ **

 

The dark leather belt sits on the bed; curled in on itself, snakelike, and contrasting sharply with the white of the bedspread.

“Just five strokes to start with,” murmurs Blaine. “Just five. You can handle that, Kurt, I promise. It’ll be so hot-"  
  
Kurt reaches for Blaine's hand, interlacing their fingers. This simple action still sends shivers up Kurt's spine, even after all this time.    
  
“I trust you,” he says automatically.  
  
He’s so close to meaning it that he can let himself believe it.

 _Potential energy,_ Ms. Hautz had written _. The stored energy of an object at rest._

Kurt drops his eyes to the belt again.    
  
 

**_0000_ **

 

Despite the sickening _hiss-snap_ of the belt as it shoves aside the air molecules in its path, there isn’t a lot of force behind the first blow.

They had discussed this ahead of time; they had agreed that the act was supposed to be about trust and intimacy, about submission and surrender. Pain is not the objective, although a little of it is unavoidable.  
  
Kurt winces; closing his eyes. _You can do this_ , he says, steeling himself. _You can do this for Blaine._

 _Kinetic energy_ , she’d written beneath the first definition. _The energy of an object in motion._  
  
The belt is drawn back again and Kurt tenses, preparing himself.   
  
 

**_0000_ **

 

Kurt bites back a whimper as the second blow strikes. Every part of him seems to flood with heat; a sick-red swath of it climbing across his skin. _This isn’t right; this doesn’t feel good._

But he hears Blaine let out a low, unmistakably sexual groan – evidence that at least one of them is enjoying this.  
  
It’s enough to make Kurt brace himself, to keep himself silent, and to focus solely on his boyfriend's pleasure.  
  
_Thermal energy,_ she had written. _Thermal energy in transit is called heat. _

He bends his head down and feels warmth flood his face.   
  


**0000**

 

The next time the belt snaps forward, _whip-sharp_ , against rapidly-reddening skin, it’s followed by the sound of a high, pained cry.

 

**_0000_ **

 

 _Elastic energy_ , she writes _, the energy stored in objects that are bent, compressed, stretched, or twisted._

 _“_ When force is applied to elastic materials,” she explains, “they’re generally capable of recovering their original shape.”  
  
She pauses.  
  
“But _all_ materials have a maximum amount of distortion they can endure without breaking. And if broken, their structure is irreversibly altered.”  
  
Kurt watches the slow drag of the second hand on its endless orbit around the edge of the clock.

“The term for that,” she says, turning to write on the board, “is elastic limit.”

 

**_0000_ **

 

The cry permeates the room; it claws outward from the throat of the boy kneeling over the bed and seeps into the mattress, the walls, and the floors.  
  
_Sound energy,_ she’d written. _The energy produced by auditory vibrations, measured in both pressure and intensity-_

“December,” says Kurt, shaking and terrified. “December, _December_. Blaine, _please_ , it hurts too much-"

 

**_0000_ **

 

Blaine twists around, blinking up at Kurt uncertainly. “Kurt, I’m fine; it feels _good_. I couldn’t help making noise. It was just a reflex-"  
  
Kurt drops the belt.  
  
He forces his fingers to unclench. He can feel the sweat trickling down his palm; until now he'd had no idea that he'd been gripping the leather that tightly.

“It _hurts,”_ he repeats in a quavering voice, and Blaine moves off the bed as quickly as he can, wincing in pain and hissing as the sheets brush against his struck skin.  
  
“Kurt?” he says hesitantly, approaching him.  
  
“Blaine,” he whispers, as if reassuring himself that the boy next to him is real and intact.  
  
“I’m _fine_ ,” says Blaine emphatically. “Kurt, come on, it’s okay, you didn’t hurt me-"  
  
“I’m not fine,” says Kurt. “Me. _I’m_ not fine, Blaine.”  
  
“Kurt-"  
  
“I felt like… god, I felt like one of the kids at school who used to-"

“It was nothing like that.”  
  
“It was _exactly_ like that,” he insists, his face crumpling. “You made the same sounds I made when they’d kick me or shove me. I - I felt like it was happening to me all over again, and at the same time I felt like I was doing those things to you. I felt like a monster.”  
  
The expression in Blaine’s eyes is one of dawning comprehension and dismay.

“Oh, Kurt,” he says, sounding horrified, reaching out gently to touch his shoulder. “I’m sorry. I’m so sorry.”  
  
He shakes his head, shoulders trembling beneath Blaine’s touch. “I can’t hurt you,” he says, sounding panicked. “God, please don’t _ever_ ask me to hurt you, Blaine. You just _can't_ ask that of me; it's too - god, I _still_ feel so-"  
  
Kurt’s voice breaks, the sentence ending abruptly, and Blaine gathers a now-crying Kurt into his arms.

“Don’t let go of me,” begs Kurt.  
  
“Never,” says Blaine, trying to cover as much of Kurt’s skin as he can with his own; trying to bind their bodies as tightly as possible. “I’ll never.”  
  
_Gravitational energy,_ she had written towards the bottom of the whiteboard. _The energy by which objects or masses are drawn together._

They stand there, pressed chest-to-chest, until Kurt feels his racing heartbeat slow to match Blaine's steady rhythm. They stand there until he can breathe again.   
  


**_0000_ **

 

They lie next to one another on the bed; Kurt resting comfortably on his back and Blaine lying semi-comfortably on his stomach.  
  
Kurt looks over at Blaine, willing his eyes not to linger on the raised, red marks he'd carved into his boyfriend's skin.  
  
_Luminous energy_ , she had written.  _The perceived energy of light._

He focuses instead on the sight of the setting sun coming in through the window and painting broad, blossoming brush-strokes across Blaine's back and shoulders. Blaine smiles wanly at him and Kurt's heart clenches at the realization that, in the millions of years of human history, there has _never_ been anyone more beautiful.   
  
  
  ** _0000_**

 

“Blaine?”  
  
“Yeah?”  
  
“Why – why did you want to be…?”  
  
Kurt shifts restlessly and Blaine follows Kurt with his eyes; angles himself toward him like a sunflower seeking out the sun’s rays.  
  
“Why did I want to be… what?” asks Blaine, his tone gentle and encouraging as he moves in closer, tracing gentle patterns on Kurt's stomach with his hand.  
  
“Hit,” replies Kurt flatly, eyes averted.  
  
Blaine shakes his head. “Kurt, it was such a stupid idea. I never should have asked you to do that.”  
  
Kurt shrugs. “I don’t know if that’s true. I mean, I want you to be able to talk to me about anything. If there are things that… excite you, I want to know about them.”  
  
Blaine gives Kurt a long, measuring look. “Okay, but can I ask you something?”

“Yes,” answers Kurt somewhat warily.  
  
“Did you know before we started that you wouldn’t like it? Or – I should clarify – did you have a pretty good idea?”  
  
Kurt fidgets slightly, and after a moment’s pause replies: “Yes.”  
  
Blaine removes his hand from Kurt’s abdomen and props himself up on his elbows. “So then why would you - ?”  
  
“Well, I – I thought I should give it a try before rejecting it outright.”

Blaine continues to gaze at him curiously, as though he knows there’s more to the story.  
  
“And…” admits Kurt reluctantly. “I suppose there was a part of me that thought that if I didn’t like it, you’d…”  
  
“I’d what?”  
  
“…find someone who would, maybe?”  
  
Blaine shakes his head. “Kurt, _no_. And I have to say, I’m pretty offended that you even thought that.”  
  
Kurt squirms guiltily. “I’m sorry.”  
  
“Look, it’s perfectly fine that you don’t like spanking. It’s just – it’s a kink I have that you _don’t_ have, simple as that. I’m sure there’s something you think is sexy that I think is absolute lunacy.”  
  
Kurt rolls his eyes. “Oh, gee, thanks.”  
  
“No, come on. I just meant-"  
  
“I know what you meant,” he says, smiling a little.  
  
“And I’ll tell you right now, Kurt,” says Blaine seriously, “that I’m not going to feel comfortable sharing these types of things with you if I think you’ll react like this; if I think you’ll go along with something out of some misguided desire to please me.”  
  
“You think it’s misguided to want to make my boyfriend happy?”  
  
“Of course not,” says Blaine. “But I think you’re missing the fairly crucial point that my happiness is contingent on yours.”  
  
Kurt nods slowly. “I get it.”  
  
Blaine shakes his head. “I don’t know if you really do.”  
  
Kurt curls his body around Blaine’s, intertwining their limbs. “Remind me?” he asks quietly, breath fluttering gently against Blaine’s cheek.  
  
_Restoring force_ , Kurt had diligently copied from the whiteboard _. The energy that brings a disturbed system back toward equilibrium._  
  
Blaine tips his face up and draws Kurt down into a kiss; soft and slow and tender.   
  
  
  **0000**

 

“I’m sorry – Ms. Hautz?” asks a girl. “Did you go over how energy forms? I don’t have that in my notes.”  
  
“It might surprise you to learn that energy can’t be created or destroyed. It just _is_. We don’t understand exactly how or why that works."  
  
Kurt raises a skeptical eyebrow at his teacher. He understands that concept fairly well, actually. He finishes copying down the last of the definitions and begins shading a beautifully drawn heart, in the center of which is scripted: _BWA & KEH_  
  
He glances at the clock again and sees that it's 2:38. Blaine is in chemistry right now.  
  
Kurt can't wait to see Blaine on Friday night, because at that point he'll have a couple of important things to tell him:

One. He'll have _aced_ his physics test.  
  
And two. Although they'd agreed to consider last week's experiment a failure, further analysis has revealed an unexpected result:  
  
Kurt knows now that there isn't a force in the universe capable of destroying their system's equilibrium.  
  
  
**_FIN_**

 


End file.
